We present progress to develop low-cost interdigitated back contact solar cells with pc-Si/SiO2/c-Si passivated contacts formed by plasma immersion ion implantation (PIII). PIII is a lower-cost implantation technique than traditional beam line implantation due to its simpler design, lower operating costs, and ability to run high doses (1E14-1E18 cm(-2)) at low ion energies (20 eV-10 keV). These benefits make PHI ideal for high throughput production of patterned passivated contacts, where high-dose, low-energy implantations are made into thin (20-200 nm) a-Si layers instead of into the wafer itself. For this work symmetric passivated contact test structures (similar to 100 nm thick) grown on n-Cz wafers with pH(3) PIII doping gave implied open circuit voltage (iV(oc)) values of 730 mV with J(o) values of 2 fA/cm(2). Samples doped with B2H6 gave iV(oc) values of 690 mV and J(o) values of 24 fA/cm(2), outperforming BF3 doping, which gave iV(oc), values in the 660-680 mV range. Samples were further characterized by SIMS, photoluminescence, TEM, EELS, and post-metallization TLM to reveal micro- and macro-scopic structural, chemical and electrical information. Published by Elsevier B.V.